Thermoplastic polyolefin (TPO) based roofing membranes are one of many types of roofing membranes available on the market today. TPO may be a melt blend or reactor blend of a polyolefin plastic, such as a polypropylene polymer, with an olefin copolymer elastomer (OCE), such as an ethylene-propylene rubber (EPR) or an ethylene-propylene-diene rubber (EPDR). Examples of commercially available TPO membranes include SURE WELD™ (Carlisle Inc.), GENFLEX™ (Omnova Solutions, Inc), ULTRAPLY™ (Firestone Building Products) and EVERGUARD TPO™ (GAF). Stretchable TPO membranes are disclosed in U.S. Pat. No. 7,666,491, which is incorporated by reference herein. Various approaches have been suggested for installing TPO membranes to a roof substrate, including mechanical fastening or adhesion.